Which must be a whole number?
A. The time it takes to drive 300 miles at 55 mph
B. The area of a circle with a radius of 5 feet
C. The area of a triangle with base of 15 and height of 9
D. The number of books in 12 bookstores
Would one of those bookstores have 1/2 of a book?
the area of a circle with a radius of 5 feet
25 pi
Bidyut
It was just lucky I saw your question. Please pose questions as new questions, not as replies to old questions.
To determine which option must be a whole number, let's analyze each choice:
A. The time it takes to drive 300 miles at 55 mph: To calculate the time, divide the distance by the speed. So, 300 miles ÷ 55 mph = 5.45 hours. Since time is typically measured in whole numbers (hours, minutes, etc.), this option is not a whole number.
B. The area of a circle with a radius of 5 feet: The formula to calculate the area of a circle is π * r^2, where π is approximately 3.14 and r is the radius. Therefore, the area of this circle would be approximately 3.14 * 5^2 = 3.14 * 25 = 78.5 square feet. Since area is typically measured in whole numbers or fractions, this option is not a whole number.
C. The area of a triangle with a base of 15 and height of 9: The formula to calculate the area of a triangle is 0.5 * base * height. So, 0.5 * 15 * 9 = 67.5. Similar to the previous example, since area is usually measured in whole numbers or fractions, this option is not a whole number.
D. The number of books in 12 bookstores: The number of books in a store is typically a whole number. Since there cannot be a fraction of a book, this option must be a whole number.
In conclusion, the option that must be a whole number is D. The number of books in 12 bookstores.